A zoom lens allows you to frame distant objects without getting too close.
Imagine the following scenarios...
1. Borrowed from a friend who is an amazing shot...
2. From a recent holiday we took:
How would you think these photos were taken. I doubt that the bird perched and posed for Garmia to take a photo or the two gentlemen posed just for me...
The first thing to note is the framing in both pictures. Only the subjects of interest are in. Everything else is out. This is key.
The bird sitting on a rock. The two gentlemen are talking. Thats it.
Subjects are sensitive. You can't get too close to fill the lens with the subject. You need to be far away.
So.. once again.. you've decided on the ah moment.. I want to capture this bird sitting on this rock. You see the frame in your head.
Shit.. I can't get closer.. so then you take out your zoom lens, turn the knob until you see exactly the frame you want from a distance that is comfortable for the subject.
A zoom lens allows you to frame distant objects without getting too close. End of story.